Separating device



Sept. 19, 1939. o. E. ElssMANN SEPARATING DEVI CE Filed sept. f1, 193s rizve oswam amm Hagnau Patented Sept. 19, 1939 UNITED STATES 2,173,088SEPARATING DEVICE Oswald Erich Eissmann, Richmond, Va., assignerUniverselle Cigarettenmaschinenfabrik J. C. Mller & Co., Dresden,Germany Application September 1, 1936, Serial No. 98,917 In GermanySeptember 19, 1935 1 Claim.

, The present invention relates to improvements in separating devices,and relates more particularly to a device designed for segregating theheavy rib portions from the leaf portions of l 5 tobacco plants.

It is an, object of the invention to provide a pneumatic arrangement forachieving a rapid and effective separation of the ribs from the `leafportions in which the separation will be clean-cut l and unaccompaniedby any admixture of these two elements. Such admixture would impair thevalue of the commercial product.

A further object of the invention is to achieve this separation by -asimple mechanism, simply and economically operated.

With the foregoing and other objects in view, the invention will be morefully described hereinafter, and will be more particularly pointed outin the claim appended hereto. l

In the drawing, the figure is a vertical longitudinal section takensubstantially centrally through a separating device embodying thefeatures of the present invention.

Referring more particularly to the drawing the leaf portions of thetobacco are fed by the obliquely ascending endless conveyor belt 3. Thisconveyor belt 3 runs over a` lower roller not shown in the figure, as itis well known, and over an upper roller illustrated in the iigure.

This upper conveyor belt roller 5 is situated in approximately thehorizontal central portion of the base of an uptake air channel 6. Suchchannel is preferably rectangular in horizontal cross-section. Invertical cross-section, the air uptake channel 6 is frusto-conical withsmooth walls.' This air channel-6 progresses from a relatively Widebase, at or about which the conveyor enters, upwardly in constantlydiminishing crosssection to an upper truncated portion of minimumlcross-section, which connectskwith an elbow or curved section 1 turningsubstantially horizontally and entering the separating chamber 8.

Above the guide roller 5 of the conveyor there is disposed in the airchannel 6 a partition 9,

the lower end of which is spaced a distance above the upper run of theconveyor. The walls of this partition are smooth and preferablystraight. Between the lower end. of the partition and the upper run ofthe conveyor belt is a slot III of desiredcross-section through whichthe material carried upwardly by the conveyor moves, as indicated by thearrow. f

'I'he partition 9 is placed obliquely, that is at anv angleto thevertical, and inclining upwardly 55 toward the right or toward the inputside of the arriving material'. By this arrangement there results anarrow passage II at the right side of the upper end of partition 9, anda wider passageor mouth I2 at the left side of the par- 50 tition 9.

(ol. zoe-139) Adjoining the guide roller 5 is an air aperture I 3, whichaperture is at the base of the left channel or the channel to the leftof the partition 9, which channel has the wide mouth I2 at the topthereof. Below, and communicating with the air aperture I3 is an aircannel I4 rising from a chamber\or space I5.

The separation chamber 8 has therein a sieve or screen I5 forming therear wall of such chamber 8. This sieve or screen is placed obliquelyand it is disposed opposite an inclined chamber wall I1. The two wallsI6 and I1 form substantially a funnel.

At the lower constricted end of the funnel is a discharge opening I8leading to a sluice I9. The sluice discharges into a pipe 20, a funnel2l and into a receiving box 22. Behind the sieve or screen wall I6 thereis a suction chamber in ywhich suction is produced by means of a suctionpipe 23 connected with the chamber as indicated at 24. Preferably thissuction chamber 30 is separated from the screen chamberl 3| by apartition wall 32, which wall has an opening 25 placing the chambers 30and 3l in communication. The opening 25 is in the upper part of the wall32. The suction pipe line 23 leads to the suction blower 26. The suctionblower discharges through a pipe line 21 `to a dust lter not shown.

In the operation of the invention, the material on the belt 3 iselevated by such belt into the separating device. This material iscaused to pass through the slot I0 between the conveyor belt and thepartition 9 and it thereby comes under the influence of the current ofsuction air which is being drawn by the blower 26 upwardly from thespace I5 through the channel I4, inlet port I3 and into the uptake airchannel 6. 'I'his suction of air, as represented by the arrows in thefigure, rises through the channel 6, passes about the elbow 1 and entersthe separation chamber 8; whereupon it passes through the screen I6,aperture 25, port 24 and into .the trunk 23 by which it passes to thesuction blower 26.

The'channel I4 guides and conflnes the upwardly entering air and, byreason of itsscrosssection, determines the speed of ow. Such air currentsweeps the material upwardly, except the heaviest rib portions which aresuiciently heavy to drop down through the channel I4 and into the spaceI5. The lighter portions of the material will become entrained with theascending air currents. Due to the progressively enlarging left channelsuch air currents will be influenced to undergo a swirling action, asindicated by the arrows, just above the widened mouth I2. This swirlingaction takes place in a circulating or eddying manner and has the effectto move the heavier rib portions of the entrained material over towardthe right or against the right wall of the conical passage 6. In otherwords the heavier rib portions are shifted over by this eddying actionto a position directly above the smaller mouth II of the right sectionof the air channel.

At this point the upward air pressure is at a minimum, or itis much lessthan above the mouth I2, and consequently such heavier rib portions inthe eddying current are permitted to drop down through the aperture IIand upon the conveyor belt 3, whereby they are introduced anew throughthe slot I0 into the current of suction air. The light ribfree leafportions, on the other hand, are carried along upwardly in the airchannel 6, through the elbow'I and into the receiving chamber 8. Suchparts of this material as reach the sieve or screen I6 will slide downthe inclined wall of this screen and be deflected to the exit openingI8. Such of this leaf material as encounters the other opposite wall I1will also be guided downwardly thereby to, and out through, the exitopening I8. 'I'he dust which is picked up and entrained with the.current of air in the intermingling swirling motion given the tobaccoleaves is drawn oir but the suction through the sieve or screen I6,carried down the trunk 23 to the blower 26, driven out the trunk 21 andrequired to pass through the dust-separating filter.

The novel points of the invention might be summarized as follows:

(a) The arrangement of a suction blower connected to the separationchamber 8 for the purpose of creating a current of suction air, whichdraws the air through a channel ll'having its air inlet aperture I3adjacent the material inlet I0.

(b) 'Ihe shaping of the perpendicular crosssection of the channel 6 as asmooth-walled cone having agentle tapering toward the leaf outlet end,and. in connection with this channel, the arrangement of the materialintroducing device (in this instance the conveyor) with its dischargingend disposed in a central portion of the base part of the channel, andcooperating with the partition 9 spaced above this discharge end of theconveyor and inclining upwardly and toward the Y side on which thematerial is introduced.

(c) The arrangement of the air inlet I3 and the air supply channel I4which is directed downwardly adjacent the point where the material isintroduced, and below this air channel I4 a space I5 for the receptionof the rib portions which have dropped down by gravity even against theinfluence of this rising air current.

(d) Isofar as the receiving or separation chamber 8 is concerned, thearrangement of the obliquely placed sieve or screen I6 with the suctionpipe line connected behind the same in combination with the oppositelysituated 0bliquely placed wall I1, both walls forming a funnel at whoseoutlet aperture there is located a sluice for the sluicing out of thetobacco leaves which trickle down'the funnel. A

It is not to be understood that the invention is J, limited to acombinationvof al1 four of the"above items but each item is believed tobe novel in l current of air while at the same time such partitioncreates a sub-division of spaces or compartments in the cone 6 such asto promote the segregation of the rib portions. The chamber 8, whichreceives the rib-free leaf portions which issue from the upper end ofthe channel B is itself fashioned as a funnel in which the arrivingleaves are conducted downwardly, one of the funnel walls serving as adust-separating sieve or screen, and with such compartment there isconnected the well known sluice for the discharge of the tobacco whichdescends by gravity therein.

In certain cases, a door 35, may be provided and when this is open theair ilow at the part where the arrows 36 are shown in the gure, may beregulated, and then certain of the leaves or stems may drop here to becarried along by some later air current, and thereby separation isaided.

Reference is made to my co-pending application, Serial Number 88,712,filed July 3, 1936, for a Tobacco sorting and separating machine.

It is obvious that various changes and modications may be made in thevdetails of construction and design of the above specifically describedembodiment of this invention without departing from the spirit thereof,such changes and modifications being restricted only by the scope of thefollowing claim.

What is claimed is:

In a separating device for shredded tobacco, a housing having an inletportion with upwardly converging walls substantially equidistantl,Yspaced from a vertical axis, a conveyor for t0- bacco leading throughone side,'of the housing and extending into substantially the centralportion of the lower end of the said inlet portion and cooperating withthe adjacent housing wall to'effect a substantial closing of theconveyor in the side of the inlet portion during normal operation, avertical partition disposed intermediately in the lower end of theupwardly converging inlet portion and extending upwardly from the innerend of the conveyor at an inclination toward the housing side wallrising from the conveyor, the partition terminating at its upper end inspaced relation to said wall and providing at one side a downwardlyflaring lateral passage above the conveyor and at its other sideproviding an upwardly aring main branch passage leading into the upperend of the inlet portionV above the partition and having its lowersmaller end adjacent the inner end of the conveyor, said housing havinga vertical passage of a cross-sectional area not greater than andopening upwardly into the lower end of said main branch passage of theinlet portion, vand air stream inducing means connected to the upper endof the inlet portion for creating an air stream upwardly through themain branch passage past the conveyor for drawing the tobacco upwardlytherefrom into said A oswALD ERICH ErssMANN.

